Does anyone have a recommendation for a work flow for georeferencing high resolution aerial photography using open source tools? Comparison of user friendliness and robustness between Quantum GIS versus GDAL?

It's a bit out of date, but the basic elements are there: find matching points between your image and a reference map (I'd now recommend http://getlatlon.com in favor the one at http://gorissen.info), use gdal_translate to knock up a virtual raster, and then you're basically done in the sense that the resulting VRT file can be converted to the GeoTIFF or tile of your choice.

I'm doing a lot with this right now, including collaborating with Tim Waters on the excellent server-side Map Warper mentioned in this thread, so there may be some new stuff in the near future loosely based on some experiments I did in JS last year: http://mike.teczno.com/notes/canvas-warp.html

Michal, very cool thanks! I was curious of how to find the pixel location and you mention that you used Photoshop's info palette, which is helpful. I think I can get away with using a 1st order transformation. Thanks for all the info!
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speshAug 3 '10 at 15:40

I find QGis's georeferencer to be pretty decent for a point and click tool. I wrote a little guide - image georeferencing with QGIS - which is slightly Canadian data-source specific, but walks through all the steps you need to get an arbitrary map into QGis.